Freezing of gait (FoG) is a common problem in people with Parkinson's disease and causes loss of mobility, falls and decreased quality of life. FoG is mysterious, the clinical phenomenon not fully characterized, the pathophysiology unknown and empirical treatment largely ineffective. The goal of this workshop on FoG is to increase understanding of FoG and to stimulate interest and research on the phenomenon. The ultimate goal is better treatment for patients with FoG. Clinicians interested in FoG and basic scientists interested in motor control, balance and locomotion will gather to examine the clinical phenomenology of FoG, explore basic physiological mechanisms of balance and locomotion that might relate to FoG and to explore the many hypotheses as to the pathogenesis of FoG. Because the workshop will be small with limited attendance, the major outcome of the meeting will be one or more reviews of the topic that will be the first review(s) on this topic and will be a "state of the clinical and basic science" relevant to FoG.